Over the last twenty years, the wireless telecommunications market has seen tremendous growth, including the use of contraband mobile wireless devices in correctional facilities or unauthorized use of such devices in other secure facilities, such as government offices. These devices are often smuggled into correctional facilities or other secure facilities and made available to unauthorized users, including inmates, which may use them to continue criminal enterprises outside the facility, threaten witnesses, and harass victims. Use of such devices may also pose a continued security risk in a correctional facility because the inmates may use them to coordinate inmate riots or direct retribution on guards, police or government officials.
It is difficult to prevent the smuggling of mobile wireless devices into correctional or other secure facilities because of commercial technology improvements and the variety of smuggling techniques available to unauthorized users and inmates. The improvements in commercial technology have reduced the size of mobile wireless devices and eased the challenges of smuggling or even accidentally carrying a mobile wireless device into a facility. Also, the accessibility of less expensive mobile wireless devices has placed these devices within the financial reach of most inmates or other unauthorized users. Though institutional security measurements are in place to attempt to prevent the smuggling of contraband into correctional facilities, the range of smuggling methods available to deliver contraband mobile wireless devices into the facility makes it difficult or even impossible to stop the flow. Inmates may coordinate smuggling efforts with visitors who move in and out of the facilities. Visiting friends and family are commonly involved in introducing contraband. Smugglers even employ methods such as throwing handsets over facility walls or fences, or concealing them in packages sent to the facility. Physical security measures alone may not be sufficient to prevent the introduction of mobile wireless devices into correction facilities or other secure facilities.
As smuggling cannot be reasonably prevented, alternative methods have been developed that focus on finding mobile wireless devices that are already inside the facilities. For example, some systems detect and locate contraband devices, which can then be confiscated. Often these systems include fixed, portable and handheld detection systems, but they can be expensive to acquire and require significant effort and personnel cost to use effectively. Their operational efficacy also is related to the effort that the facility invests in time, training, and technology. An increased effort from the facility may improve results, but it may also increase operational costs.
Because a cell phone's benefit to the user is its ability to access the commercial wireless network, denying the cell phone access to the wireless network may be a better approach to reduce the risks posed by contraband cell phones and other mobile wireless devices. The device is benign without access to the commercial wireless network. A range of technology based approaches have been developed and are available to limit an unauthorized device's access to the commercial wireless network. These approaches include jammer technologies and access management approaches. There are several types of jammers, but they are typically designed to disrupt the communications of the device with the wireless communications network. One type of access management approach is a Managed Access System (MAS), which employs a private wireless network within a facility to provide wireless network access to authorized cell phones within the system's range. Authorized devices are provided access to voice and data services while unauthorized devices are denied access.
Another type of system, an Access Denial Service (ADS) works cooperatively with the commercial wireless network to deny access to unauthorized devices within a facility. An ADS system uses the interaction between cell phones and the network to determine if the cell phone is within a facility or not. When a cell phone is detected within the facility, the carrier is notified and if the device is not authorized for operation in the facility, it is prevented from future access to the wireless network by the carrier.
There are drawbacks to such systems. Geolocation devices alone will not provide sufficient detail on the device identification to enable action by the commercial service provider. Managed Access Systems may provide insufficient information to determine the location of a cellular device that has registered to their network. They can typically only identify that a device has attached, what has attached, and when it has attached. At best, it can identify which sector of a distributed antenna system the attachment has occurred. The system typically needs to operate on a persistent basis using fixed location, autonomous sensors.